Effective Satellite Selection Methods for RTK-GNSS NLOS Exclusion in Dense Urban Environments

H. Tokura, N. Kubo

Peer Reviewed

Abstract:	In recent years, many applications have required highly precise positioning. The use of the Global Navigation Satellite System (GNSS) provides the absolute three-dimensional (3D) position. By adding information for corrections, GNSS can potentially provide a positioning accuracy at the centimeter scale. In an urban environment, GNSS receivers easily receive multipath signals. These multipath effects eliminate the number of received satellites and degrade the quality of the solution. If the multipath signal can be removed and good-condition signals can be selected, more accurate solutions can be obtained. Based on this idea, this paper proposes two satellite selection methods based on using a fisheye view images and the ratio value provided during the ambiguity resolution process. The first method determines non-line-of-sight (NLOS) or line-of-sight (LOS) satellites based on a photo taken with the fisheye lens. The second method searches for optimum satellite combinations based on the ratio value provided by the ambiguity resolution. Multipath signals often cause the incorrect integer ambiguities. The basic idea of this method is to determine correct integer ambiguities by removing multipath signals. To evaluate the proposed methods, static tests were performed in a severe multipath environment. For the future tasks, we are investigating the possibility using precise 3D building maps to select good satellite. At the conference presentation, those results will be presented.
Published in:	Proceedings of the 29th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2016) September 12 - 16, 2016 Oregon Convention Center Portland, Oregon
Pages:	304 - 312
Cite this article:	Tokura, H., Kubo, N., "Effective Satellite Selection Methods for RTK-GNSS NLOS Exclusion in Dense Urban Environments," Proceedings of the 29th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2016), Portland, Oregon, September 2016, pp. 304-312. https://doi.org/10.33012/2016.14801
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